<template>
	<div class="helper">
		<span class="left">{{unFinishedTodoLength}} items left</span>
		<span class="tabs">
			<span 
				v-for="state in states"
				:key="state"
				:class="[state,filter === state ? 'actived' : '']"
				@click="toggleFilter(state)"
			>
				{{state}}
			</span>
		</span>
		<span class="clear" @click=clearAllCompleted>Clear Completed</span>
	</div>
</template>

<script>
	export default {
		props:{
			filter:{
				type: String,
				required: true
			},
            todos:{
                type:Array,
                required: true
            }
		},
		data(){
			return {
				states:['all','active','completed']
			}
		},
        computed:{
            unFinishedTodoLength(){
                return this.todos.filter(todo => !todo.completed).length
            }
        },
		methods:{
			clearAllCompleted(){
                this.$emit('clearAllCompleted')
            },
			toggleFilter(state){
                this.$emit('toggle',state)
            }
		}
	}
</script>

<style lang="stylus" scoped>
    .helper{
        font-weight 100
        display flex
        justify-content space-between
        padding 5px 0
        line-height 30px
        background-color #ffffff
        font-size 14px
        font-smoothing:antialiased;
    }
    .left,.clear,.tabs{
        padding 0px 10px
        box-sizing border-box
    }
    .left,.clear{
        width 150px
    }
    .left{
        text-align left
    }
    .clear {
        text-align:right
        cursor pointer
    }
    .tabs{
        width 200px
        display flex
        justify-content space-around
        *{
            display inline-block
            padding 0px 10px
            cursor pointer
            border 1px solid rgba(175,47,47,0)
            &.actived{
                border-color rgba(175,47,47,0.4)
                border-radius 5px
            }
        }
    }
</style>